JSON Formatter — Paste & Validate

Format, validate, and convert JSON you paste — processing happens on your device, no access to your browsing.

JSON Formatter — Paste & Validate is a paste-in, paste-out JSON tool that never touches the page you're on. PRIVATE BY DESIGN This extension asks for zero access to your browsing. There are no content scripts and no host permissions — it cannot read the tabs you have open, the sites you visit, or anything on the page. You open the popup, paste JSON in, and get formatted output back. Every byte of processing — parsing, formatting, validation, highlighting — happens locally in your browser. Nothing you paste is ever sent anywhere. This extension collects no data of any kind — no analytics, no tracking, no telemetry. The only network traffic it ever makes is a purchase-verification check with ExtensionPay if you choose to upgrade. FREE, AND GENUINELY USEFUL • Format: pretty-print with your choice of 2-space, 4-space, or tab indent, applied instantly as you paste. • Validate with exact error location: invalid JSON gets a precise line and column, a caret pointing at the exact character, and a plain-English explanation (like "trailing comma before }") instead of a cryptic parser message. • Syntax highlighting on the formatted result, so nested structures are easy to scan. • Minify with one click when you need compact output. • Sort keys recursively to make two JSON blobs easier to diff by eye or normalize inconsistent API responses. • Copy the result to your clipboard or download it as a file. • Your indent style, sort-keys default, and light/dark theme are remembered between sessions. PREMIUM ($5 one-time) For people who work with JSON all day, a one-time $5 upgrade adds: • A collapsible tree view with search/filter and one-click copy of any node's JSON path. • JSON to CSV and JSON to YAML conversion, both directions. • A structural diff view that shows added, removed, and changed keys between two JSON documents side by side. No subscription, no account required, no recurring charge — pay once, keep the premium features. Whether you're inspecting an API response, cleaning up a config file, or debugging a webhook payload, this extension does the job without ever asking to see what's on your screen.